Process of recovering waste fibrous material



Patented Feb. 14,1928.

UNITED. STATES, PATENT OFFICE.

I LESTER KIRSCHBBAU'N, OF CHICAGO, ILLINOIS.

I PROCESS OF BECOVEBING WASTE FIBBQUS KATEBIAL' no Drawing. Application filed August 16, 1922, Serial no. 5822307. Renewed June so, 1926.

This invention relates to improvements and processes of recovering fibrous material and refuse, more particularly to the treatment of waste scrap paper containing bitumen, pitches, or the like, in. the manufacture of fibrous sheets whiclrare inpregnated, saturated or coated with a bituminous or pitchy binder in which it is difiicult if not commercially impractical to reuse the waste In scrap material because of the diificulty in separating the fibre from the binder. If, on the other hand, the-bituminous material is not separated from the fibre, it tends to clog the cylinder moulds and prevents the l-normal operation of the paper machine.

is therefore necessary to remove the binder from the fibre if-the latter is to be reused.

In addition to fibrous sheets which are-saturated, impregnated or coated in "the usual way with asphalt, waterproof sheets are'now being made in which the bituminous emulsion is mixed with a fibre stock'pri'or to the stock being felted on the paper'machine; An emulsion of the character referred to may bemade in accordance with my prior PatentNo. 1.417335. This emulsion as setforth in said pat ent may consist of suitable bituminous binder and colloidal clay and water. m The present invention is directed to the se 'aarationof the bitumen from the fibre in .wastematerial whether the bitumen be applied to the fibre in the ordinary way, or is applied in accordance with a process set forth in my prior patentabove referred to. y In carrying out the present invention the wastep'aper containing the bitumen is put in' a suitable macerator or. disintegrator' with water and the bentonite is then added.

40 The amount of bentonite will depend upon the character and amount of asphalt and other bitumen contained in the paper, but with most grades of saturated or impreg nated paper, from ten to twen vpercent of bentonite will be suflicient. Th s mixture is beaten up and macerated while kept in a relatively thick mass and at an elevated temperature, s 'y 100 to 200 Fahrenheit. This pa er "machine.

of soda, in s It flocculation.

taining a bituminous material, consisting in Operation tends to release the pitch or other bitumen from the fibre and the bitumen 60 tends to form an emulsion with the bentonite. The emulsion so formedwill be miscible in water .and will not tend to clog up the ccordin lythe'material can be mixed with other b're stock and put back into the heaters of the paper machine and then run in the usual manner. However, before putting the material back into the heaters of the paper machine, it is' desirable to add a co enti such as alum, or silicate flocculating a cient percentages to produce 1' In some cases it may be desirableito separate the bitumen from the fibre by sub'ect-"65 ing the mixture both tothe action of eat and pressure. -Where pressure .is used a steam pressure will be generated of lbs.

per square inch, more or less.- The action of the heat and pressure will'tend tomor'e readily treat the bituminous saturated material referred to and the use of pressure isparticularly adapted where the material is of 'a refractory nature; as for example, where there is an excess ofhigh melting point coating, or the like. Where pressure 1s used, the material should be thoroughly agitated so as to effect the desired detergent action.

out y adding small quantities of caustic sodaor soda ash.

I claim as my inv ntion:

1. A process of treating fibrous stock containing a bituminous material, consisting in subjecting the same to the detergent action of bentonite in the presence of water at an elevated temperature and under pressure to separate the bituminous material from the fibres and 'form an emulsion with the hentonite.

2. A. process of treating fibrous stock con-- subject the same to the detergent ac on of bentomte in the presence of water at an In addition to the use of bentonite the. 80 e 1 fore oing cooking operation may be carried 'elevatedftemperatureiand under ressureto" Vateil temperature and under as'uperatmos- 10 separate the bituminous material from the pheric pressure. -fibres. and form an emulsionl with the ben- 4. A. process of treating fibrous stock contonite, the bituminous material c0nstituttaining a pitchy material, comprising sub- 5 ing the internal phase.- A jecting same to the action of an argillaceous 3. A process of treating fibrous stock condetergent'and an alkali, in the presence of )5 taining a pitchy material, comprising subwater at an elevated temperature and under jecting'same to'the action of an argillaceous a superatmospheric pressure.-

detergent in the presence of water at an ele-'. LESTER KIRSCHBRAUN. 

